Immunohistochemistry of cellular proliferation in eyes with longstanding retinal detachment.

To further characterize the content and nature of cyclitic membranes (n = 4), ringschwielen (n = 3) and a subretinal strand on sections of complete globes with long-standing retinal detachment after trauma (n = 7) or retinal reattachment surgery (n = 1), we applied a panel of cellular and extracellular antibodies using the APAAP (alkaline phosphatase and monoclonal anti-alkaline phosphatase) technique. Only one cyclitic membrane from an eye that was enucleated two months after trauma was positive for glial fibrillary acidic protein, demonstrating the presence of glial cells. All cyclitic membranes contained macrophages and expressed intracellular contractile proteins. Ringschwielen stained consistently for cells of epithelial origin (RPE) with cytokeratin and for macrophages. The subretinal strand stained for cytokeratin, macrophages and alpha-smooth muscle actin, supporting cellular contraction in the genesis of this form of proliferative vitreoretinopathy.